[ELI5] Can one physically compress water, like with a cyclinder of water with a hydraulic press on the top, completely water tight, pressing down on it, and what would happen to the water?

Question

[ELI5] Can one physically compress water, like with a cyclinder of water with a hydraulic press on the top, completely water tight, pressing down on it, and what would happen to the water?

In: 1967

Answer 1

We regularly compress water in diamond vices, where the changing structure of the water can be studied through the diamond as the pressure is increased to enormous levels:
https://www.sciencealert.com/scientists-finally-study-strange-black-superionic-ice-that-could-exist-on-alien-worlds

Essentially, under these conditions, water forms rare structures that are described as “ice” but which are extremely hot and cannot exist under normal pressures.